# -- HoH.pl --
#!/usr/bin/perl -w
use strict;
use Data::Dumper;
use hash;
print Dumper($HoH);    # refer to the imported variable



# -- hash.pm --
package hash;

our @EXPORT = '$HoH';  # export your variable $HoH
use base "Exporter";

our $HoH = {
         'HASH_1' => {
                item_a => "abc",
                item_b => "123",
                item_c => "blue",
        },
        'HASH_2' => {
                item_a => "xyz",
                item_b => "789",
                item_c => "white",
        },
        'HASH_3' => {
                item_a => "ijk",
                item_b => "3.14",
                item_c => "yellow",
        }
};

1;
[download]

However there is a problem with the above approach, what happens if another package also exports $HoH? There is a possibility of name collision. I would rather encapsulate the HoH variable inside a hash object instead:

# -- HoH.pl --
#!/usr/bin/perl -w
use strict;
use Data::Dumper;
use hash;

my $h = new hash;
print Dumper($h->HoH);



# -- hash.pm --
package hash;

my $HoH = {
        'HASH_1' => {
                item_a => "abc",
                item_b => "123",
                item_c => "blue",
        },
        'HASH_2' => {
                item_a => "xyz",
                item_b => "789",
                item_c => "white",
        },
        'HASH_3' => {
                item_a => "ijk",
                item_b => "3.14",
                item_c => "yellow",
        }
};

sub new
{
    my $class = shift;
    bless {}, $class;
}

sub HoH
{
    # my $class = shift;
    $HoH  # the HoH method returns hash reference
}

1;
[download]

Update: Or using do as demonstrated by Coruscate below, of course.